Proteomic analysis of grapevine (Vitis vinifera L.) tissues subjected to herbicide stress

Two-dimensional gel electrophoresis coupled to mass spectrometry analysis was used to examine for the first time the effect of a herbicide (flumioxazin) on a crop species (Vitis vinifera L.) at the proteome level. Examination of 2-D maps derived from chemically stressed tissues revealed the presence of 33 spots displaying a differential expression pattern. The presence of stress responsive proteins in the different plant organs analysed suggests that flumioxazin could act systemically. Among the responsive proteins, some photosynthesis-related proteins, including several fragments of the enzyme Rubisco, were identified. This effect suggests that photosynthesis could be impaired by the herbicide. The induction of several enzymatic antioxidant systems was also observed, probably as a result of an oxidative stress. Moreover, the photorespiration pathway was stimulated, as suggested by the induction of some key enzymes involved in this process. Changes in carbon metabolism-associated proteins presumably reflect altered patterns of carbon flux in response to impaired photosynthesis and an increased need for osmotic adjustment in affected tissues. Finally, plant defences were stimulated as revealed by the induction of a set of proteins belonging to the pathogenesis-related 10 class, suggesting that they could play an essential role in cell defence mechanisms against flumioxazin.